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991.
Viviane Dumur Radj Gervais Jean-Marc Rigot Elisabeth Delomel-Vinner Bertrand Decaestecker Jean-Jacques Lafitte Philippe Roussel 《Human genetics》1996,97(1):7-10
To assess better the link between congenital bilateral absence of the vas deferens (CBAVD) and cystic fibrosis (CF), we compared sweat chloride values, analysis of the CFTR intron 8 poly(T) tract length and analysis of 10 exons in a population of 38 patients with CBAVD. The data indicate that this population can be divided into three groups of patients. In the first group of 15 patients with abnormal sweat chloride (> 60 mmol/l), the frequency of CF mutations is high. In the second group of 18 patients with equivocal sweat chloride (between 40 and 60 mmol/l), the frequency of the 5T variant is high; 6 patients have a F508 mutation and a 5T variant and 1 patient is homozygous for the 5T variant; a 5T variant has been detected in 3 other patients, and a F508 mutation in another patient. A third group of 5 patients is probably not related to CF: these patients have other congenital abnormalities of the urogenital tract, low chloride values (< 40 mmol/l) and apparently no abnormality of the CF gene. 相似文献
992.
Purification and characterization of a novel protease from culture filtrates of a Streptomyces sp. 总被引:2,自引:0,他引:2
993.
The variations of leaf carbohydrate concentration, carbon isotopediscrimination () of leaf soluble carbohydrate, gas-exchangeand growth during a soil drying cycle under 350 and 700 µmolmol-1 CO2 concentrations ([CO2]) inQuercus robur seedlings wereanalysed. In well-watered conditions, a doubling of [CO2] causedan increase of CO2 assimilation rate (A) ( +47%) and a decreaseof stomatal conductance for water vapour (g) (25%),anddoubled the intrinsic water-use efficiency (A/g). The valuesof A were not affected by elevated [CO2] which was consistentwith the 2-fold increase of A/g. Elevated [CO2 also significantlyincreased sucrose and starch leaf concentrations as well asaerial growth and plant dry weight. The stimulating effect ofCO2 enrichment on A and A/g was maintained in moderate droughtconditions, but disappeared in the most severe drought conditions.Drought induced an increase of hexose concentrations in both[CO2], but this effect was more pronounced under elevated [CO2],which may contribute to increase osmoregulation. From the onsetof drought, starch was depleted in both [CO2]. Carbon isotopediscrimination decreased in response to drought, which correspondedto an increase in A/g according to the two-step model of isotopicdiscrimination. In contrast, the A/g values derived from instantaneousleaf gas-exchange measurements decreased along the drying cycle.The discrepancy observed between the two independent estimatesof water-use efficiency is discussed in terms of time-scaleintegration. The results obtained with the isotopic approachusing soluble carbohydrate suggest a predominant stomatal limitationof CO2 assimilation in response to drought. Soil drying cycle,elevated CO2, leaf gas-exchange, leaf carbohydrate concentrations,carbon isotope discrimination, growth, Quercus robur. Key words: soil drying cycle, elevated CO2, leaf gas-exchange, leaf carbohydrate concentrations, carbon isotope discrimination, growth, Quercus robur 相似文献
994.
Grard F. Blanchard Jean-Marc Guarini Philippe Gros Pierre Richard 《Journal of phycology》1997,33(5):723-728
The response of the photosynthetic capacity (Pmax) of microphytobenthos to short-term variations of temperature (in the range 5–35° C) was assessed on a seasonal basis. The relationship is described mathematically, and relevant physiological parameters are identified: PMAX, the maximum value of Pmax achieved at Topl, the optimum temperature. Estimated values of Topt do not change significantly throughout the year and remain close to 25° C. It is thus concluded that Topt is not influenced by seasonal variations in the daily range of mud surface temperature. Identical conclusions hold for Tmax (ca. 38° C), the thermal threshold beyond which no photosynthesis occurs. Conversely, PMA estimates exhibit substantial variability: PMAX (mean ± root mean square error) is highest in April (11.18 ± 0.42 [μg C · [μg Chl a]?1· h?1) during the beginning of the annual increase in temperature, photoperiod, and maximum irradiance and is lowest in December (3.04 ± 0.16 μg C · [μg Chl a]?1· h?l). From an ecological point of view, the short-term and seasonal variations of PMAX suggest that the microphytobenthic community takes advantage of the abiotic spring environmental conditions, allowing the onset of the bloom. Nevertheless, no “acclimation strategy” (i.e. shifts in Topt and Tmax that prevent temperature inhibition in summer or improve photosynthetic rates in winter) is apparent from our results. 相似文献
995.
996.
François Pelletier Christian Fonteix Aurélio Lourenço da Silva Annie Marc Jean-Marc Engasser 《Cytotechnology》1994,15(1-3):291-299
New software sensors based on the Extended Kalman Filter technique have been developed for the monitoring of animal cell perfusion cultures. They use a kinetic model describing the growth, death and metabolism of hybridoma cells as a function of the medium composition. The model was initially validated on a batch culture and found to correctly predict the continuous perfusion culture kinetics, except for the production of ammonia and lactate. Using the measurement of a single component in the culture medium, in this case glucose, the Extended Kalman Filter provides an excellent evaluation of the time variation of the concentrations of living and dead cells, of glutamine and antibodies, during the whole perfusion culture for a retained cell density rising from 1 to 11×106 cells.ml–1 inside the reactor. 相似文献
997.
998.
999.
Françoise Botterel Cécile Angebault Odile Cabaret Franziska A. Stressmann Jean-Marc Costa Frédéric Wallet Benoit Wallaert Kenneth Bruce Laurence Delhaes 《Mycopathologia》2018,183(1):171-183
Given the complexity of the airway microbiota in the respiratory tract of cystic fibrosis (CF) patients, it seems crucial to compile the most exhaustive and exact list of the microbial communities inhabiting CF airways. The aim of the present study was to compare the bacterial and fungal diversity of sputa from adult CF patients during non-exacerbation period by culture-based and molecular methods, and ultra-deep-sequencing (UDS). Sputum samples from four CF patients were cultured and analysed by DNA extractions followed by terminal restriction fragment length polymorphism analysis through resolution of bacterial ribosomal gene (rDNA) fragments, and cloning plus sequencing of part of fungal rRNA genes. These approaches were compared with UDS method targeting 16S rDNA gene and the internal transcribed spacer (ITS) 2 region of rDNA. A total of 27 bacterial and 18 fungal genera were detected from the four patients. Five (18%) and 3 (16%) genera were detected by culture for bacteria and fungi, respectively, 9 (33%) and 3 (16%) by first generation sequencing (FGS) methods, and 26 (96%) and 18 (100%) by UDS. The mean number of genera detected by UDS per patient was statistically higher than by culture or FGS methods. Patients with severe airway disease as assessed by standard spirometry exhibited a reduced fungal and bacterial diversity. UDS approach evaluates more extensively the diversity of fungal and bacterial flora compared with cultures. However, it currently remains difficult to routinely use UDS mainly because of the lack of standardization, and the current cost of this method. 相似文献
1000.
Localization of the genetic defect in multiple endocrine neoplasia type 1 within a small region of chromosome 11 总被引:18,自引:7,他引:11 下载免费PDF全文
Yusuke Nakamura Catharina Larsson Cecile Julier Camilla Bystrm Britt Skogseid Samuel Wells Kjell
berg Mary Carlson Thomas Taggart Peter O'Connell Mark Leppert Jean-Marc Lalouel Magnus Nordenskjld Ray White 《American journal of human genetics》1989,44(5):751-755
Multiple endocrine neoplasia type I (MEN-1), a Mendelian disorder with an autosomal dominant mode of inheritance, causes hyperplasia in the parathyroid glands and hyperplasia or neoplasm in the anterior pituitary gland and/or the pancreatic islets. The genetic defect responsible for MEN-1 in three families was recently mapped to the long arm of chromosome II by linkage between the MEN-1 locus and the gene for skeletal muscle glycogen phosphorylase (PYGM) at 11q13. We have constructed a genetic linkage map of seven markers in the vicinity of the MEN-1 locus that has allowed us to map more precisely the gene associated with MEN-1; the target region has been narrowed to about 12 cM. The closely linked markers will be useful also for identification of likely carriers in families in which an allele responsible for MEN-1 segregates. 相似文献